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991.
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PURPOSE: To describe the causes and outcomes of pediatric injuries using the emergency departments (ED) as a surveillance site. METHOD: Prospective, 14-day surveys of all injuries were conducted in the EDs of the two national trauma referral hospitals of Trinidad and Tobago. Data on patient demographics, type, cause, and outcome of injuries were collected. The chi 2 test for significance was used for categorical variables. RESULTS: Pediatric patients (< 20 years) accounted for 41.5% (714/1722) of injury visits. Of these, 62.6% were male and 17.4% were < four years old, 26.2% four to nine years, 31.1% 10 to 14 years, and 25.4% were 15 to 19 years old. Three patients (0.4%) died, 68.6% were discharged, and 31.0% admitted. Intentional injuries accounted for 13.9% of injuries. Of the intentional injuries, the assailant was significantly more likely to be known than not (P < 0.01). The most common causes of all injuries were: falls, 44.4%; blunt objects, 12.3%; sharp objects, 11.8%; motor vehicle (including pedestrians), 7.4%; poison, 3.6%; and burns, 1.7%. Injuries occurring in the home accounted for 46.2%; in school, 25.5%; sports/recreation, 11.1%; and at work, 4.5%. The most common injuries were: lacerations, 30.8%, contusions/abrasions, 26.7%, fractures, 18.8%; and sprains/dislocations, 9.4%. CONCLUSION: Pediatric injuries are a significant cause of morbidity and mortality in this country, accounting for almost one third of injured patients. Because of the low frequency of pediatric injury deaths, ED surveillance may be a more effective means of identifying high risk groups and activities for injuries. Data from EDs may be useful in other developing countries to develop injury prevention programs.  相似文献   
994.
Moexipril is a prodrug which is hydrolysed after oral administration to its active metabolite moexiprilat, an inhibitor of the angiotensin converting enzyme (ACE). Once daily administration of moexipril 7.5 or 15 mg effectively reduces blood pressure in patients with essential hypertension (including the elderly and postmenopausal women with this condition). In double-blind randomised comparative studies, moexipril 7.5 to 15 mg once daily showed similar efficacy to other antihypertensive agents, including captopril, hydrochlorothiazide, atenolol, metoprolol, sustained release verapamil and nitrendipine. Combined therapy with hydrochlorothiazide and moexipril had a significantly greater antihypertensive effect than either agent alone. Moexipril is well tolerated by the majority of patients and compares well in this respect with other antihypertensive agents. Its tolerability profile appears to be characteristic of ACE inhibitors as a class (the most common adverse events being headache, symptoms of upper respiratory tract infection and cough). Moexipril generally had no clinically significant effect on lipid, glucose or electrolyte metabolism or haematological parameters, and, in particular, it was not associated with any significant changes in lipid or glucose metabolism in postmenopausal women (with or without hormone replacement therapy). CONCLUSIONS: Once daily moexipril is a useful agent for the treatment of essential hypertension, which compares well with currently available options in terms of clinical efficacy and tolerability. In addition, clinical experience to date supports its use in postmenopausal women.  相似文献   
995.
BACKGROUND AND PURPOSE: Insulin resistance and hyperinsulinemia have been associated with atherosclerosis. Recent attention has focused on the possible role of proinsulin because most radioimmunoassays for insulin cross-react with proinsulin. Therefore, it is not known which of the two, insulin per se or proinsulin, is more strongly related to atherosclerosis. METHODS: We examined the relation between fasting proinsulin, fasting split proinsulin, fasting and 2-hour insulin (after oral glucose load), and intima-media wall thickness (IMT) in the common carotid artery (CCA) and internal carotid artery (ICA) in 985 nondiabetic subjects from the Insulin Resistance Atherosclerosis Study, a multiethnic study of insulin resistance and atherosclerosis. RESULTS: In the overall population, a weak but significant relation between proinsulin and CCA IMT was observed (r=0.07, P=0.029). However, the relation between proinsulin and IMT was stronger in Hispanics and non-Hispanic whites than in African Americans. In non-Hispanic whites and Hispanics, significant correlations between CCA and proinsulin (r=0.087) and between ICA and proinsulin (r=0.101), split proinsulin (r = 0.092), and fasting insulin (r = 0.087) were observed. The significant correlations became more attenuated (and nonsignificant) after adjustment for cardiovascular risk factors, especially plasminogen activator inhibitor-1 (PAI-1). CONCLUSIONS: The association between proinsulin and IMT, while weak, appears to be stronger than the association between insulin and IMT. Adjustment for PAI-1 markedly attenuated the association between proinsulin and IMT, suggesting a possible mediating role for PAI-1 in this association. It is possible that proinsulin may represent a marker of atherosclerosis rather than a causal factor for atherosclerosis. Studies of the insulin resistance syndrome and atherosclerosis that use insulin as a surrogate for insulin resistance should consider the use of specific insulin assays as well as determination of proinsulin concentrations.  相似文献   
996.
The Griffonia simplicifolia-I (GS-I) isolectins have been used to probe the effect of lectin valence on their high-affinity binding to human erythrocytes. These tetrameric lectins are composed of A and B subunits and constitute a series of five isolectins (A4, A3B, A2B2, AB3, B4). The A subunit is specific for alpha-D-GalNAc end groups and binds to the blood type A determinant GalNAcalpha1, as well as to terminal alpha-D-Gal groups found on type B cells. The B subunit is specific for alpha-D-Gal end groups, and binds very specifically to type B erythrocytes. This series of isolectins is tetravalent (A4), trivalent (A3B), divalent (A2B2), and monovalent (AB3) for type A erythrocytes; thus, this system provides the opportunity to examine the effect of lectin valency on the association constants of these GS-I isolectins binding to cells. Cell binding experiments carried out using 125I-labeled GS-I isolectins and type A human erythrocytes allowed us to demonstrate that (1) the association constant of the isolectin monovalent for alpha-D-GalNAc (AB3) is virtually identical to its association constant for the haptenic sugar methyl-N-acetyl-alpha-D-galactosaminide, reported previously, and (2) the association constant of the GS-I isolectins for human type A erythrocytes increases with increasing valency of the isolectin. These results indicate that the increased affinity displayed by the GS-I isolectins for human type A erythrocytes is dependent on their multivalency, and not on an extended binding site nor on nonspecific, or noncarbohydrate, interactions of the lectin with the cell surface. These findings should be of general relevance to understanding the high-affinity interactions observed between other multivalent proteins and multivalent ligands (e.g., cell surfaces).  相似文献   
997.
Abdominal cocoon is a rare cause of intestinal obstruction. The authors report four cases (3 boys, 1 girl; age range, 6 to 8 years) that presented with features of intestinal obstruction. There was no history of previous surgery, peritonitis, or prolonged drug intake in any of these cases. One patient presented with acute intestinal obstruction and gangrene of bowel. The etiology, preoperative diagnosis, and management of this condition are discussed.  相似文献   
998.
999.
Chlorine is typically used within drinking water distribution systems to maintain a disinfectant residual and minimize biological regrowth. Typical distribution system models describe the loss of disinfectant due to reactions within the water matrix as first order with respect to chlorine concentration, with the reactants in excess. Recent work, however, has investigated relatively simple dynamic models that include a second, hypothetical reactive species. This work extends these latter models to account for discontinuities associated with rechlorination events, such as those caused by booster chlorination and by mixing at distribution system junction nodes. Mathematical arguments show that the reactive species model will always represent chlorine decay better than, or as well as, a first-order model, under single dose or rechlorination conditions; this result is confirmed by experiments on five different natural waters, and is further shown that the reactive species model can be significantly better under some rechlorination conditions. Trihalomethane (THM) formation was also monitored, and results show that a linear relationship between total THM (TTHM) formation and chlorine demand is appropriate under both single dose and rechlorination conditions. This linear relationship was estimated using the modeled chlorine demand from a calibrated reactive species model, and using the measured chlorine demand, both of which adequately represented the TTHM formation.  相似文献   
1000.
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